The field of this invention is analyte detection, particularly reagent systems for use in analyte detection.
Analyte detection in physiological fluids, e.g., blood or blood derived products, is of ever increasing importance to today""s society. Analyte detection assays find use in a variety of applications, including clinical laboratory testing, home testing, etc., where the results of such testing play a prominent role in diagnosis and management in a variety of disease conditions. Analytes of interest include glucose, alcohol, formaldehyde, L-glutamie acid, glycerol, galactose, glycated proteins, creatinine, ketone body, ascorbic acid, lactic acid, leucine, malic acid, pyruvic acid and uric acid, steroids, etc. In response to this growing importance of analyte detection, a variety of analyte detection protocols and devices for both clinical and home use have been developed.
Many of the protocols and devices that have been developed to date employ a signal producing system to identify the presence of the analyte of interest in a physiological sample, such as blood. One type of signal producing system that finds use in the detection of a variety of different analytes is one in which an oxidase or a peroxidase enzyme oxidizes the analyte of interest and produces hydrogen peroxide. The hydrogen peroxide is then detected by subsequent enzyme-catalyzed reaction with a dye substrate to produce a detectable chromogenic product. Dyes useful in such signal producing systems generally yield a visible color signal with high sensitivity.
A variety of highly sensitive dyes are commonly used in peroxide producing signal producing systems. However, many highly sensitive dyes such as urea derivative dyes are limited by their stability (e.g., to oxidation, light) in the solid phase and/or in solution.
While compositions containing highly sensitive dyes have been developed, there continues to be a need for the further development of such compositions. For example, solid phase compositions that include highly sensitive urea derivative dyes and are resistant to oxidation would be of great interest.
Patents of interest include: JP 1118768; JP 9019296; EP 38 205, EP 124 287 and EP 251297. See also, Yagi et al. (1986) Biochem. Int. 12:367-371.
Compositions, reagent test strips, analyte detection systems and kits of the same, as well as methods for their use in the detection of an analyte in a sample, are provided. The subject compositions are characterized by having a positively charged porous matrix and a urea derivative dye on at least one surface of the matrix, where in many preferred embodiments the urea derivative dye is a negatively charged urea derivative dye. In many preferred embodiments, the subject compositions further include at least one additional reagent member of a peroxide producing signal producing system, e.g., an analyte oxidase and/or a peroxidase. The subject compositions, test strips, analyte detection systems and kits find use in the detection of a wide variety of analytes in a sample, such as a physiological sample, e.g., blood or a fraction thereof.